Electrical transport properties of graphite sheets doped polyvinylidene fluoride nanocomposites

Graphite nanosheets (GNs) were introduced into polyvinylidene fluoride (PVDF) via the solution mixing technique. The nanocomposites were then subjected to compression molding for electrical measurements. Solution mixing enabled homogeneous dispersion of GN within the PVDF matrix. The electrical transport behavior of such nanocomposites was studied by means of the impedance spectroscopy in a wide frequency range from 10² to 10⁷ Hz. The results showed that the permittivity and conductivity of the composites are frequency dependent and well obeyed with the scaling law (ε′ ∝ ω^u and σ′ ∝ ω^−v) in the vicinity of percolation threshold (Φ_c ≈ 2.5 wt%). A large dielectric constant of 173 was observed in the PVDF/GN 2.5 wt% composites at 1 kHz.